'30 Rock' trailer

Vacation’s over, Liz Lemon. The trailer for the upcoming sixth season of 30 Rock teases that everyone’s favorite “Night Cheese” crooner has got a secret that apparently only Kelsey Grammer can get to the bottom of. (Maybe he’ll also be running against Jack Donaghy for mayor of New York. Twist!) So what’s being kept so hush-hush? That she’s playing (and/or possibly cheering) for the WNBA team the New York Liberty? That her behavior has gotten so erratic (singing in public, grabbing her own boobs in an elevator) that even Tracy Jordan is concerned? We’ll have to wait until Thursday, Jan. 12, to find out. Until then, check out the promo, nerds: